Hello Sakshi

My recommendation is too not think about your aim of 99%. Because if you get it, you will be happy and if not then sad. But if you don't have any expectations, there would be no surprises to deal with.

Anyways, to get 99% in Class 10th board exams, you will need the combo of Hardwork + Luck. As hardwork alone would not be enough (you can get strict checking in boards, some question may come out of syllabus etc).

You will need to be consistent and study regularly. For you, Discipline > Motivation. Give your 100% and you will definitely get good grades.

Thank You!!!